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    <title>Document</title>
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    <div id="root">
    <div>
      请输入张三的成绩: <input type="text" v-model="score">
      <h2 v-if="score>=90">张三的成绩优秀</h2>
      <h2 v-else-if="score>=75">张三的成绩良好</h2>
      <h2 v-else-if="score>=60">张三的成绩及格</h2>
      <h2 v-else-if="score<60">张三的成绩不及格</h2>
    </div>
     
    </div>
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  <script>
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    new Vue({
      el: "#root",
      data() {
        return {
          score:null
        }
      },
    });
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